Chapter 3. Installing and configuring ReaR

Before you back up the undercloud and the overcloud control plane nodes, you must first install and configure Relax and Recover (ReaR) on the undercloud and on each control plane node.

3.1. Installing the required packages

You must install the Relax and Recover (ReaR) packages and packages for generating ISO images on the undercloud node and on each control plane node.

Procedure

  1. Install the required packages on the undercloud and on each control plane node. For example:

    [root@controller-x ~]# dnf install rear genisoimage nfs-utils -y
  2. Create a backup directory on the undercloud and on each control plane node. For example:

    [root@controller-x ~]# mkdir -p /ctl_plane_backups
  3. Mount the ctl_plane_backups NFS directory from the backup node running NFS on the undercloud and on each control plane node. For example:

    [root@controller-x ~]# mount -t nfs  <ip-addr>:/ctl_plane_backups /ctl_plane_backups

    Replace <ip-addr> with the IP address of the backup node running the NFS server.

3.2. Creating the configuration files

As the root user on the undercloud and on each control plane node, perform the following steps:

  1. Create the ReaR configuration file:

    [root@controller-x ~]# mkdir -p /etc/rear
    [root@controller-x ~]# tee -a "/etc/rear/local.conf" > /dev/null <<'EOF'
    OUTPUT=ISO
    OUTPUT_URL=nfs://<ip-addr>/ctl_plane_backups
    ISO_PREFIX=<SERVER_NAME-X>
    BACKUP=NETFS
    BACKUP_PROG_COMPRESS_OPTIONS=( --gzip )
    BACKUP_PROG_COMPRESS_SUFFIX=".gz"
    BACKUP_PROG_EXCLUDE=( '/tmp/*' '/data/*' )
    BACKUP_URL=nfs://<ip-addr>/ctl_plane_backups
    BACKUP_PROG_EXCLUDE=("${BACKUP_PROG_EXCLUDE[@]}" '/media' '/var/tmp' '/var/crash')
    BACKUP_PROG_OPTIONS+=( --anchored --xattrs-include='*.*' --xattrs )
    EOF

    Replace <SERVER_NAME-X> with the hostname of the node. For example, if the node hostname is controller-0, replace <SERVER_NAME-X> with controller-0. Replace <ip-addr> with the IP address of the backup node running the NFS server configured in Chapter 2, Preparing the backup node.

    Important

    If the undercloud or control plane nodes use UEFI as their boot mode, you must add USING_UEFI_BOOTLOADER=1 to the configuration file too.

  2. Create the rescue.conf file:

    [root@controller-x ~]# tee  -a "/etc/rear/rescue.conf" > /dev/null <<'EOF'
    BACKUP_PROG_OPTIONS+=( --anchored --xattrs-include='*.*' --xattrs )
    EOF